Diff: hash/SHA1.cpp

Revision:

7:2dbbdfb08123

Parent:

6:19aa835f2bbb

Child:

10:bc9c23aa3870

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hash/SHA1.cpp	Sat Sep 14 18:21:32 2013 +0000
@@ -0,0 +1,221 @@
+/**
+    Implementation of SHA-1 as described here:
+    http://tools.ietf.org/html/rfc1319
+*/
+
+#include "SHA1.h"
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#define F0(B,C,D) ((B & C) | ((~B) & D))
+#define F1(B,C,D) (B ^ C ^ D)
+#define F2(B,C,D) ((B & C) | (B & D) | (C & D))
+#define ROTL(W,N) (((W) << N) | ((W) >> (32-N)))
+                        
+static const uint32_t K0 = 0x5A827999;
+static const uint32_t K1 = 0x6ED9EBA1;
+static const uint32_t K2 = 0x8F1BBCDC;
+static const uint32_t K3 = 0xCA62C1D6;
+
+
+static const uint32_t H0 = 0x67452301;
+static const uint32_t H1 = 0xEFCDAB89;
+static const uint32_t H2 = 0x98BADCFE;
+static const uint32_t H3 = 0x10325476;
+static const uint32_t H4 = 0xC3D2E1F0;
+
+static const uint32_t MASK = 0xF;
+
+#define W(s) ( w[s] = ROTL(w[((s) + 13) & MASK] ^ w[((s) + 8) & MASK] ^ w[((s) + 2) & MASK] ^ w[s],1))
+
+#define R0(A,B,C,D,E,T) E += ROTL(A, 5) + F0(B, C, D) + w[T] + K0; \
+                        B = ROTL(B,30);
+#define R1(A,B,C,D,E,T) E += ROTL(A, 5) + F0(B, C, D) + W(T & MASK) + K0; \
+                        B = ROTL(B,30); 
+#define R2(A,B,C,D,E,T) E += ROTL(A, 5) + F1(B, C, D) + W(T & MASK) + K1; \
+                        B = ROTL(B,30); 
+#define R3(A,B,C,D,E,T) E += ROTL(A, 5) + F2(B, C, D) + W(T & MASK) + K2; \
+                        B = ROTL(B,30); 
+#define R4(A,B,C,D,E,T) E += ROTL(A, 5) + F1(B, C, D) + W(T & MASK) + K3; \
+                        B = ROTL(B,30); 
+
+                        
+SHA1::SHA1():
+HashAlgorithm(),
+h0(H0),
+h1(H1),
+h2(H2),
+h3(H3),
+h4(H4),
+totalBufferLength(0),
+buffer(),
+bufferLength(0)
+{
+}
+
+uint8_t SHA1::outputSize() const
+{
+    return 20;
+}
+
+void SHA1::update(uint8_t *data, uint32_t length)
+{
+    if(length < 64-bufferLength)
+    {
+        memcpy(&buffer[bufferLength], data, length);
+        bufferLength += length;
+        totalBufferLength += length;
+        return;
+    }
+    int offset = 64-bufferLength;
+    memcpy(&buffer[bufferLength], data, offset);
+    computeBlock(&h0,&h1,&h2,&h3,&h4, buffer);
+    while(length-offset > 64)
+    {
+        memcpy(buffer, &data[offset], 64);
+        computeBlock(&h0,&h1,&h2,&h3,&h4, buffer);
+        offset += 64;
+    }
+    if(offset > length)
+        offset -= 64;
+    bufferLength = length - offset;
+    memcpy(buffer, &data[offset], bufferLength);
+    totalBufferLength += length;
+}
+
+void SHA1::finalize(uint8_t *hash)
+{
+    uint32_t *hash2 = (uint32_t*)hash;
+    uint16_t padding;
+    if(totalBufferLength % 64 < 56)
+        padding = 56 - (totalBufferLength % 64);
+    else
+        padding = 56 + (64 - (totalBufferLength % 64));
+        
+    buffer[bufferLength++] = 0x80;
+    padding--;
+    if(padding+bufferLength == 56)
+        memset(&buffer[bufferLength], 0, padding);
+    else
+    {
+        memset(&buffer[bufferLength], 0, 64-bufferLength);
+        computeBlock(&h0,&h1,&h2,&h3,&h4, buffer);
+        memset(buffer, 0, 56);
+    }
+    
+    uint64_t lengthBit = totalBufferLength << 3;
+    uint32_t lengthBitLow = lengthBit;
+    uint32_t lengthBitHigh = lengthBit >> 32;
+    lengthBitLow = __rev(lengthBitLow);
+    lengthBitHigh = __rev(lengthBitHigh);
+    memcpy(&buffer[56], &lengthBitHigh, 4);
+    memcpy(&buffer[60], &lengthBitLow, 4);
+    computeBlock(&h0,&h1,&h2,&h3,&h4, buffer);
+    
+    hash2[0] = __rev(h0);
+    hash2[1] = __rev(h1);
+    hash2[2] = __rev(h2);
+    hash2[3] = __rev(h3);
+    hash2[4] = __rev(h4);
+    
+    // reset state
+    h0 = H0;
+    h1 = H1;
+    h2 = H2;
+    h3 = H3;
+    h4 = H4;
+    totalBufferLength = 0;
+    bufferLength = 0;
+}
+
+
+void SHA1::computeHash(uint8_t *hash, uint8_t *data, uint32_t length)
+{
+    uint32_t *hash2 = (uint32_t*)hash;
+    uint64_t lengthBit = length << 3;
+    uint32_t padding;
+    if(length % 64 < 56)
+        padding = 56 - (length % 64);
+    else
+        padding = 56 + (64 - (length % 64));
+        
+    uint32_t h0 = H0, h1 = H1, h2 = H2, h3 = H3, h4 = H4;
+    while(length >= 64)
+    {
+        computeBlock(&h0,&h1,&h2,&h3,&h4, data);
+        length -= 64;
+        data += 64;
+    }
+   
+    uint8_t buffer[64];
+    memcpy(buffer, data, length);
+    buffer[length++] = 0x80;
+    padding--;
+    if(padding+length+8 == 64)
+        memset(&buffer[length], 0, padding);
+    else
+    {
+        memset(&buffer[length], 0, 64-length);
+        computeBlock(&h0,&h1,&h2,&h3,&h4, buffer);
+        memset(buffer, 0, 56);
+    }
+
+    uint32_t lengthBitLow = lengthBit;
+    uint32_t lengthBitHigh = lengthBit >> 32;
+    lengthBitLow = __rev(lengthBitLow);
+    lengthBitHigh = __rev(lengthBitHigh);
+    memcpy(&buffer[60], &lengthBitLow, 4);
+    memcpy(&buffer[56], &lengthBitHigh, 4);
+    
+    computeBlock(&h0,&h1,&h2,&h3,&h4, buffer);
+
+    hash2[0] = __rev(h0);
+    hash2[1] = __rev(h1);
+    hash2[2] = __rev(h2);
+    hash2[3] = __rev(h3);
+    hash2[4] = __rev(h4);
+}
+
+void SHA1::computeBlock(uint32_t *h02, uint32_t *h12, uint32_t *h22, uint32_t *h32, uint32_t *h42, uint8_t *buffer)
+{
+    uint32_t *buffer2 = (uint32_t*)buffer;
+    uint32_t w[16];
+    for(int t = 0; t < 16; ++t)
+        w[t] = __rev(buffer2[t]);
+    
+    uint32_t a = *h02, b = *h12, c = *h22, d = *h32, e = *h42;
+    
+    R0(a,b,c,d,e, 0) R0(e,a,b,c,d, 1) R0(d,e,a,b,c, 2) R0(c,d,e,a,b, 3)
+    R0(b,c,d,e,a, 4) R0(a,b,c,d,e, 5) R0(e,a,b,c,d, 6) R0(d,e,a,b,c, 7)
+    R0(c,d,e,a,b, 8) R0(b,c,d,e,a, 9) R0(a,b,c,d,e,10) R0(e,a,b,c,d,11)
+    R0(d,e,a,b,c,12) R0(c,d,e,a,b,13) R0(b,c,d,e,a,14) R0(a,b,c,d,e,15)
+    R1(e,a,b,c,d,16) R1(d,e,a,b,c,17) R1(c,d,e,a,b,18) R1(b,c,d,e,a,19)    
+    
+    
+    R2(a,b,c,d,e,20) R2(e,a,b,c,d,21) R2(d,e,a,b,c,22) R2(c,d,e,a,b,23)
+    R2(b,c,d,e,a,24) R2(a,b,c,d,e,25) R2(e,a,b,c,d,26) R2(d,e,a,b,c,27)
+    R2(c,d,e,a,b,28) R2(b,c,d,e,a,29) R2(a,b,c,d,e,30) R2(e,a,b,c,d,31)
+    R2(d,e,a,b,c,32) R2(c,d,e,a,b,33) R2(b,c,d,e,a,34) R2(a,b,c,d,e,35)
+    R2(e,a,b,c,d,36) R2(d,e,a,b,c,37) R2(c,d,e,a,b,38) R2(b,c,d,e,a,39)    
+    
+    R3(a,b,c,d,e,40) R3(e,a,b,c,d,41) R3(d,e,a,b,c,42) R3(c,d,e,a,b,43)
+    R3(b,c,d,e,a,44) R3(a,b,c,d,e,45) R3(e,a,b,c,d,46) R3(d,e,a,b,c,47)
+    R3(c,d,e,a,b,48) R3(b,c,d,e,a,49) R3(a,b,c,d,e,50) R3(e,a,b,c,d,51)
+    R3(d,e,a,b,c,52) R3(c,d,e,a,b,53) R3(b,c,d,e,a,54) R3(a,b,c,d,e,55)
+    R3(e,a,b,c,d,56) R3(d,e,a,b,c,57) R3(c,d,e,a,b,58) R3(b,c,d,e,a,59)    
+    
+    
+    R4(a,b,c,d,e,60) R4(e,a,b,c,d,61) R4(d,e,a,b,c,62) R4(c,d,e,a,b,63)
+    R4(b,c,d,e,a,64) R4(a,b,c,d,e,65) R4(e,a,b,c,d,66) R4(d,e,a,b,c,67)
+    R4(c,d,e,a,b,68) R4(b,c,d,e,a,69) R4(a,b,c,d,e,70) R4(e,a,b,c,d,71)
+    R4(d,e,a,b,c,72) R4(c,d,e,a,b,73) R4(b,c,d,e,a,74) R4(a,b,c,d,e,75)
+    R4(e,a,b,c,d,76) R4(d,e,a,b,c,77) R4(c,d,e,a,b,78) R4(b,c,d,e,a,79)    
+        
+    *h02 += a;
+    *h12 += b;
+    *h22 += c;
+    *h32 += d;
+    *h42 += e;
+}
+